A family of novel, acidic N-glycans in Bowes melanoma tissue plasminogen activator have L2/HNK-1-bearing antennae, many with sulfation of the fucosylated chitobiose core.

摘要: A family of about 20 novel acidic bi- and tri-antennary N-glycans, amounting to almost half those expressed on Bowes melanoma tissue-plasminogen activator (t-PA) were found possess Galbeta1-->4GlcNAcbeta1-->, sulfated sialylated GalNAcbeta1-->4GlcNAcbeta1--> or GlcAbeta1--> 3Galbeta1-->4GlcNAcbeta1--> antennae, which containing GlcA, depicting the L2/HNK-1 carbohydrate epitope, preferentially located 6 arm. proportion glycans highly charged, because multiple variously distributed sulfation, some was fucosylated chitobiose core. Multiple expression epitope a single glycan observed. The most abundant compound biantennary carrying GlcA 6-branched antenna an alpha2-->6 GalNAc other. N-glycosylation sequon Asn448, is known express all sulfate-carrying N-glycans contains, unusually, arginine residue. An electrostatic interaction between this cationic amino acid core-sulfate group N-glycan proposed reduce mobility in region t-PA active site. Because 'brain-type' nature described neuro-ectodermal cell line, possibility neural interacting with L2/HNK-1-recognizing molecule, laminin, central nervous system extracellular matrix discussed.